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#ifndef TRAJECTORY_ROLLOUT_MAP_GRID_H_
#define TRAJECTORY_ROLLOUT_MAP_GRID_H_

#include <vector>
#include <iostream>
#include <base_local_planner/trajectory_inc.h>
#include <ros/console.h>
#include <ros/ros.h>

#include <base_local_planner/map_cell.h>
#include <costmap_2d/costmap_2d.h>
#include <geometry_msgs/PoseStamped.h>

namespace base_local_planner
{
/**
 * @class MapGrid
 * @brief A grid of MapCell cells that is used to propagate path and goal distances for the trajectory controller.
 */
class MapGrid
{
public:
    /**
     * @brief  Creates a 0x0 map by default
     */
    MapGrid();

    /**
     * @brief  Creates a map of size_x by size_y
     * @param size_x The width of the map
     * @param size_y The height of the map
     */
    MapGrid(unsigned int size_x, unsigned int size_y);

    /**
     * @brief  Returns a map cell accessed by (col, row)
     * @param x The x coordinate of the cell
     * @param y The y coordinate of the cell
     * @return A reference to the desired cell
     */
    inline MapCell &operator()(unsigned int x, unsigned int y) { return map_[size_x_ * y + x]; }

    /**
     * @brief  Returns a map cell accessed by (col, row)
     * @param x The x coordinate of the cell
     * @param y The y coordinate of the cell
     * @return A copy of the desired cell
     */
    inline MapCell operator()(unsigned int x, unsigned int y) const { return map_[size_x_ * y + x]; }

    inline MapCell &getCell(unsigned int x, unsigned int y) { return map_[size_x_ * y + x]; }

    /**
     * @brief  Destructor for a MapGrid
     */
    ~MapGrid() {}

    /**
     * @brief  Copy constructor for a MapGrid
     * @param mg The MapGrid to copy
     */
    MapGrid(const MapGrid &mg);

    /**
     * @brief  Assignment operator for a MapGrid
     * @param mg The MapGrid to assign from
     */
    MapGrid &operator=(const MapGrid &mg);

    /**
     * @brief reset path distance fields for all cells
     */
    void resetPathDist();

    /** 检查我们是否需要调整大小
     * @brief  check if we need to resize
     * @param size_x The desired width
     * @param size_y The desired height
     */
    void sizeCheck(unsigned int size_x, unsigned int size_y);

    /**
     * @brief Utility to share initialization code across constructors
     */
    void commonInit();

    /**
     * @brief  Returns a 1D index into the MapCell array for a 2D index
     * @param x The desired x coordinate
     * @param y The desired y coordinate
     * @return The associated 1D index
     */
    size_t getIndex(int x, int y);

    /**
     * return a value that indicates cell is in obstacle
     */
    inline double obstacleCosts() { return map_.size(); }

    /**
     * returns a value indicating cell was not reached by wavefront
     * propagation of set cells. (is behind walls, regarding the region covered by grid)
     */
    inline double unreachableCellCosts() { return map_.size() + 1; }

    /**
     * @brief  Used to update the distance of a cell in path distance computation
     * @param  current_cell The cell we're currently in
     * @param  check_cell The cell to be updated
     */
    inline bool updatePathCell(MapCell *current_cell, MapCell *check_cell, const costmap_2d::Costmap2D &costmap);

    /** 调整全局路径的分辨率使其能够达到cost_map的分辨率
     * increase global plan resolution to match that of the costmap by adding points linearly between global plan points
     * This is necessary where global planners produce plans with few points.
     * @param global_plan_in input
     * @param global_plan_output output
     * @param resolution desired distance between waypoints
     */
    static void adjustPlanResolution(const std::vector<geometry_msgs::PoseStamped> &global_plan_in,
                                     std::vector<geometry_msgs::PoseStamped> &global_plan_out, double resolution);

    /** 计算局部地图上的每一个cell与规划路径之间的距离
     * @brief  Compute the distance from each cell in the local map grid to the planned path
     * @param dist_queue A queue of the initial cells on the path
     */
    void computeTargetDistance(std::queue<MapCell *> &dist_queue, const costmap_2d::Costmap2D &costmap);

    /**
     * @brief  Compute the distance from each cell in the local map grid to the local goal point
     * @param goal_queue A queue containing the local goal cell
     */
    void computeGoalDistance(std::queue<MapCell *> &dist_queue, const costmap_2d::Costmap2D &costmap);

    /** 处理路径地图
     * @brief Update what cells are considered path based on the global plan
     */
    void setTargetCells(const costmap_2d::Costmap2D &costmap,
                        const std::vector<geometry_msgs::PoseStamped> &global_plan);

    /** 处理目标地图
     * @brief Update what cell is considered the next local goal
     */
    void setLocalGoal(const costmap_2d::Costmap2D &costmap,
                      const std::vector<geometry_msgs::PoseStamped> &global_plan);

    double goal_x_, goal_y_;       // 最后一次计算的目标距离
    unsigned int size_x_, size_y_; // 地图大小

private:

    std::vector<MapCell> map_;     // MapCells的存储

};
};

#endif
